Process of extracting copper from ores.



Patented Apr. 20, 1909..

2 BHEETS-8 HEBT 1.

wfimsms.

G. G. COLLINS.

PROCESS OP EXTEAGTING COPPER PROM ()RES.

APPLIOATIOH 11.51) 150v. 27, 1907. RENEWED SEPT. 19, 1008.

Patented Apr. 20, 1909.

- 2 SHEETS- 8151531 2.

7/////////// V//// fl////////////// CALEB e. COLLI-NS, or WOODMERE,

NEW YoRmassIeNoR TO CALVIN AMORY STEVENS, or

NEW YORK, N. Y..-

rnocnssor .nx'rnac rme corrnn FROM ORES.

Speeificati'on of Letters Patent.

Patented April 20, 1909..

Application filed November 27, 1907, Serial No. $04 189. RenewedSeptember 19, 1908. Serial No. 453,823.

To all whom it may concern:

l 3e it known that I, CALEB G. COLLINS, a c1t1zen of the United States,residing at Woodmere, Nassau county, and State of New York, haveinvented certain new and useful Im rovements in Processes for Extractingopper from Ores, of which the following is a specification.

My invention relates to the extraction of copper from its severaloresespecially the more refractory thereof, such as those containingcopper and silica, and is designed to afford an economical process bymeans of whlch practically all the copper may be separated from the oresand collected in a metallic state. V

I am aware that heretofore comminuted carbonaceous material has beenused in a closed furnace to reduce the oxids of co per to a metallicstate, but I have found rom practical investigation and-experimentationthat carbon alone is insuflicient to effect the reduction of all thecopper in the various ores, so that only imperfect results haveheretofore been attained in this respect.

My invention consists primarily in the use of carbonates of the alkaliesand alkaline earths in conjunction with, carbonaceous material in thereduction of copper ore; and secondarily in the use in conyunction withcarbonaceous material and carbonates of the alkalies and. alkalineearths, 0.1) hypochlorites of the alkalies and alkalineearths,substantially as hereinafter set forth.

Incidentally my invention includes certain other features hereindescribed and claimed.

In the accompanying drawings, Figure 1, is a top view of a furnaceadapted to the re guirements of my improved process of reucing copperore; Fig. 2,. is a horizontal section thereof, taken upon plane of line22-' Fig. 3; Fig. 3, a verticalsection taken upon plane of line 33 Fig.1;-

vertical section taken upon plane of line 4 t Fig. 1.

While I do not restrict myself to the identical form and construction offurnace shown I have found the same afiords good practical results.

R represents an elongated vertical retort chamber terminating in a waterbasin B below from which it is separated b a movable bottom I), whichmay be rocked om the exterior'by means of a bar 6, I (see Fig. 4). Theupper portion of the retort R is proabout the same vided with a hopper Hcapable of being sealed. Combustion chambers O, O, are located on eachsideof theretort chamber R, the products of combustion passing therefrominto the vertical side flues c, c, which in turn open into the end orchimney flues 0, c. It will be seen that the side flues 0, 0, and theend flues c, c, constitute practically- 'a single chamber surroundingthe greater charge to be treated is fed into the retort R by gravity orotherwise, care being taken that the hopper H is well filled to excludeair.

In practice I grind the ore to the degree .of fineness desired accordingto the hardness of the ore say, so that it will pass through 'a No. 10mesh screen. With the comminuted ore I put ground charcoal, coal orother carbonaceous material; also comminuted carbonates of the alkaliesor alkaline earths, which combination is suitable for the ores known ascuprite, malachite, and azurite. If the ore to be treated containssulfur or silicate, as bornite or chrysocolla either alone or mixed withother ores, I add to the charge hypochlorites of the alkalies oralkaline earths to break up the combination of sulfur and silica withthe copper, as otherwise such copper would pass through the furnaceWithout being reduced to the metallic state. After the retort is filledwith the charge it is sealed to exclude air. andprevent there-oxidization of the copper after it has been reduced to the metallicstate. The water seal afforded by the basin B protects the lower end ofthe retort, and by receiving and cooling the copper as it descends fromthe retort retains it in themetallic state, so that it may be collectedby any well known process of concentration. From five to twenty percent. by weight of carbonaceous material and roportion of pulverizedlime stone (calcium carbonate) may be mixed with the ground ore,according to the nature and requirements of the latter.

Where'sulfid or silicate of copper is present in the ore chlorite oflime in the proportion approximately of from 12 to 13 per cent. 0calcium hypochlorite to each 1 per cent. of sulfur in the ore maybeaddedto the combination, all the ingredients being in any casethoroughly mixed together before the charge is introduced into theretort. After the retort is charged and seale'd, fires are built in thecombustion chambers C, G, the heat being continued, the ore in theretortis brought to a bright red state of incandescenoe. The bottom I), isthen rocked and tilted to allow of the descent of the metallic copperinto the water in the basin B, Where it is cooled and from which it iscollected for concentration as before stated. The metallic copper isthus removed from time to time as may be found expedient. When themetallic copper descends into the basin B, it causes the formation ofsteam which rises into the retort where it is united with the calciumand results in the generation of internal heat which materially aids inthe reduction of the ore and eiiects a saving of fuel. In other wordsthe reduced 'metal and the angue both red hot as they drop from theurnace into the Water under the furnace generate steam which coming incontact With the red hot carbon mixed with the ore is decomposed intohydrogen and an exactly equal volume of carbon monoxid gas both of whichare when heated owerful reducers of metallic oxids and sulds to themetallic state.

Considering the process technically, the first action under influence ofheat of the mixture of copper sulfid, alkaline carbonates and carbon isto reduce copper.carbonate and calcium sul d thus:

CuCO3-l-CaS I-C =Cu+CaS+3CO.

When the carbonate and silicate of copper unmixed with or uncombinedWith sulfur is in the case the reaction is in some respects more simple,metallic copper, calcium silicate and carbon monox d gas being producedthus:

some cause not yet determined, than other copper ores of apparently thesame charac er. In cases like this I add to the m x-.

ture from five to fifteen per centi the w'eight of the copper ore ofcalcium hypochlorite or bleaching powder OaOCl in which case I thereactions may be represented thus:

GuS+CaOG1 +CaOO +C= Cu+S O,+CaCl |-CaO+CO, and where an unusually,refractory copper silicate is to be treated, thus Where there is muchsilica mixed or com.-

substituting of course the symbols of the carbonates of barium,potassium or sodlum according to which is used, When the carbonates ofbarium, potassium or sodium are used With the carbonate of calcium the"reduction of the on per ore to the metallic state, especially i the orebe silicious, is effected at a lower temperature than when the onlyalkali used is carbonate of lime, but as before indicated there are someores inwhich carbonate of calcium alone is the only alkali necessary.Where powdered limestone is used on the charge as before stated it isreduced to quicklime during the roasting process so thatthe steamevolved during the operation of dumpin a portion of the charge into thewater in the basin B, slakes the l me and thereby contributes materiallyto the heat of the sealed retort. this connection it is to be noted thatI am the first to utilize the heat of the reduced 'ore to form steamwhich is decomposed Within the retort producing hydrogen which, being ina nascent state, is most eifective 1n producing the desired chemicalreactions within the retort.

By n process I am enabled to extract practica 1y all the copper fromall'the several copper ores, and to accomplish this desirable result inthe most economical man- By the use in combination with the carbon andcarbonates of the alkaliesand alkaline earths owerful bases having astronger afinity t an copper for sulfur and silica, I renderorescontaining either or both of the lat er t ac ab nd ro ab1e, -a, result not he et for a ta ned: so far as I em aware.

What I claim as m invention nd esire to secure by Letters atent is,

1. The herein described process of separating copper from its ore whichconsists ,in mlxmg the ore in a comminuted state with comminutedcarbonaceous material, and with comminuted carbonates of the alka liesand the alkaline earths, and subjecting the mixture to heat in a closedretort.

2. The herein described process of separating copper from its ore whichconsists in mixing the ore in a comminuted state with commlnutedcarbonaceous material, and with comminuted carbonates of the alkaliesand the alkaline earths, subjecting the mixture to heat in a closedretort, and discharging the resultant metallic copper into water, forthe purpose described.

3. The herein described process of separating copper from its ore whichconsists in mixing the ore in a comminuted state with commlnutedcarbonaceous material, and

with comminuted carbonates of the alkalies and the alkaline earths,together with hypochlorites of the alkalies and the alkaline earths, andsubjecting the mixture to heat in a closed retort.

4. The herein described process of separatingcopperfrom its ore whichconsists 1n mlxing the ore in a comminuted state with comminutedcarbonaceous material, and with comminuted carbonates of the alkaliesand the alkaline earths, together with hypochlorites of the alkalies andalkaline earths subjecting the mixture to heat in a closed retort, anddischarging the resultant metallic copper into water, for the purposedescribed. 4

5. The herein described process of separating copper from its ore whichconsists in mixing the ore in a comminuted state with comminutedcarbonaceous material, and with comminuted calcium carbonate, andsubjecting the mixture to heat in a closed retort.

6. The herein described process of separating copper from its ore whichconsists in mixing theore in a comminuted state with comminutedcarbonaceous material,

and with comminuted limestone, subjecting the mixture to heat in aclosed retort, and discharging the resultant metallic copper into water,for the purpose described.

7 The herein described process of separating copper from its ore whichconsists in mixing the ore ma comminuted state with commniutedcarbonaceous material, and with commlnuted calcium carbonate comminutedand hypochlorite of calcium, subjecting the mixture to heat in a closedretort.

8. The herein described process of separating copper from its ore whichconsists in mixing the ore in a comminuted state with comminutedcarbonaceous material, and with comminuted calcium carbonate andhypochlorite of calcium, subjecting the mixture to heat in a closedretort, and discharging the resultant metallic copper into Water, forthe purpose described.

9. The herein described process of separating copper from its oreconsisting in mixing the ore in a comminuted state with comminutedcarbonaceous material and comminuted limestone, subjecting the mixtureto heat in a closed retort, and admitting steam to the retort to slakethe quicklime resultant from the heating of the limestone, for thepurpose described.

10. The herein described process of separating copper from its oreconsisting in mixing the ore in a comminuted state with comminutedcarbonaceous material and with comminuted carbonates of the alkalies.or. the alkaline earths, subjectin the mixture to heat in a closedvessel, discharging the resultant metallic copper into water, andutilizing the steam thereby generated to form hydrogen within the retortfor the purpose described.

11. The herein described process of separating copper from its oreconsisting in mixing the ore in a comminuted state with comminutedcarbonaceous material and with comminuted carbonates of the alkalies orthe alkaline earth together with hypochlorite of lime or hypochloritesof the other alkalies subjecting the mixture to heat in a closed vessel,discharging the resultant metallic copper into water, and utilizing thesteam thereby generated to form hydrogen within the retortffor thepurpose descrlbed.

12. The herein described process of separating copper from its oreconsisting 1n mixing the ore in a comminuted state wlth carbonaceousmaterial and with a base having an affinity stronger than that of thecopper for sulfur and silica, and

then subjecting the mixture to heat in a closed retort.

CALEB G. COLLINS.

Witnesses D. W. GARDNER, Gno. WM. MIA'I'I.

